Anisotropies and chemical composition of ultra-high energy cosmic rays using arrival directions measured by the Pierre Auger Observatory

The Pierre Auger Collaboration

doi:10.7529/ICRC2011/V02/0868

Anisotropies and chemical composition of ultra-high energy cosmic rays using arrival directions measured by the Pierre Auger Observatory

The Pierre Auger Collaboration

Physics

Research output: Contribution to conference › Paper › peer-review

Abstract

The Pierre Auger Collaboration has reported evidence for anisotropy in the distribution of arrival directions of the cosmic rays with energies E > E_th = 5.5×10¹⁹ eV. These show a correlation with the distribution of nearby extragalactic objects, including an apparent excess around the direction of Centaurus A. If the particles responsible for these excesses at E > E_th are heavy nuclei with charge Z, the proton component of the sources should lead to excesses in the same regions at energies E/Z. We here report the lack of anisotropies in these directions at energies above E_th/Z (for illustrative values of Z = 6, 13, 26). If the anisotropies above E_th are due to nuclei with charge Z, and under reasonable assumptions about the acceleration process, these observations imply stringent constraints on the allowed proton fraction at the lower energies.

Original language	English (US)
Pages	137-140
Number of pages	4
DOIs	https://doi.org/10.7529/ICRC2011/V02/0868
State	Published - 2011
Event	32nd International Cosmic Ray Conference, ICRC 2011 - Beijing, China Duration: Aug 11 2011 → Aug 18 2011

Other

Other	32nd International Cosmic Ray Conference, ICRC 2011
Country/Territory	China
City	Beijing
Period	8/11/11 → 8/18/11

Keywords

Anisotropies
Chemical composition
Pierre auger observatory
Ultra-high energy cosmic rays

ASJC Scopus subject areas

Nuclear and High Energy Physics

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10.7529/ICRC2011/V02/0868

Cite this

@conference{1b33c507cc85458d8ba3f306ececf62d,

title = "Anisotropies and chemical composition of ultra-high energy cosmic rays using arrival directions measured by the Pierre Auger Observatory",

abstract = "The Pierre Auger Collaboration has reported evidence for anisotropy in the distribution of arrival directions of the cosmic rays with energies E > Eth = 5.5×1019 eV. These show a correlation with the distribution of nearby extragalactic objects, including an apparent excess around the direction of Centaurus A. If the particles responsible for these excesses at E > Eth are heavy nuclei with charge Z, the proton component of the sources should lead to excesses in the same regions at energies E/Z. We here report the lack of anisotropies in these directions at energies above Eth/Z (for illustrative values of Z = 6, 13, 26). If the anisotropies above Eth are due to nuclei with charge Z, and under reasonable assumptions about the acceleration process, these observations imply stringent constraints on the allowed proton fraction at the lower energies.",

keywords = "Anisotropies, Chemical composition, Pierre auger observatory, Ultra-high energy cosmic rays",

author = "{The Pierre Auger Collaboration} and P. Abreu and M. Aglietta and Ahn, {E. J.} and Albuquerque, {I. F.M.} and D. Allard and I. Allekotte and J. Allen and P. Allison and {Alvarez Castillo}, J. and J. Alvarez-Mu{\~n}iz and M. Ambrosio and A. Aminaei and L. Anchordoqui and S. Andringa and T. Anticic and A. Anzalone and C. Aramo and E. Arganda and F. Arqueros and H. Asorey and P. Assis and J. Aublin and M. Ave and M. Avenier and G. Avila and T. B{\"a}cker and M. Balzer and Barber, {K. B.} and Barbosa, {A. F.} and R. Bardenet and Barroso, {S. L.C.} and B. Baughman and J. B{\"a}uml and Beatty, {J. J.} and Becker, {B. R.} and Becker, {K. H.} and A. Bell{\'e}toile and Bellido, {J. A.} and S. BenZvi and C. Berat and X. Bertou and Biermann, {P. L.} and P. Billoir and F. Blanco and M. Blanco and C. Bleve and H. Bl{\"u}mer and M. Boh{\'a}cov{\'a} and D. Boncioli and I. Zaw",

note = "Publisher Copyright: {\textcopyright} 2011 IOP Publishing Ltd and SISSA.; 32nd International Cosmic Ray Conference, ICRC 2011 ; Conference date: 11-08-2011 Through 18-08-2011",

year = "2011",

doi = "10.7529/ICRC2011/V02/0868",

language = "English (US)",

pages = "137--140",

}

TY - CONF

T1 - Anisotropies and chemical composition of ultra-high energy cosmic rays using arrival directions measured by the Pierre Auger Observatory

AU - The Pierre Auger Collaboration

AU - Abreu, P.

AU - Aglietta, M.

AU - Ahn, E. J.

AU - Albuquerque, I. F.M.

AU - Allard, D.

AU - Allekotte, I.

AU - Allen, J.

AU - Allison, P.

AU - Alvarez Castillo, J.

AU - Alvarez-Muñiz, J.

AU - Ambrosio, M.

AU - Aminaei, A.

AU - Anchordoqui, L.

AU - Andringa, S.

AU - Anticic, T.

AU - Anzalone, A.

AU - Aramo, C.

AU - Arganda, E.

AU - Arqueros, F.

AU - Asorey, H.

AU - Assis, P.

AU - Aublin, J.

AU - Ave, M.

AU - Avenier, M.

AU - Avila, G.

AU - Bäcker, T.

AU - Balzer, M.

AU - Barber, K. B.

AU - Barbosa, A. F.

AU - Bardenet, R.

AU - Barroso, S. L.C.

AU - Baughman, B.

AU - Bäuml, J.

AU - Beatty, J. J.

AU - Becker, B. R.

AU - Becker, K. H.

AU - Bellétoile, A.

AU - Bellido, J. A.

AU - BenZvi, S.

AU - Berat, C.

AU - Bertou, X.

AU - Biermann, P. L.

AU - Billoir, P.

AU - Blanco, F.

AU - Blanco, M.

AU - Bleve, C.

AU - Blümer, H.

AU - Bohácová, M.

AU - Boncioli, D.

AU - Zaw, I.

PY - 2011

Y1 - 2011

N2 - The Pierre Auger Collaboration has reported evidence for anisotropy in the distribution of arrival directions of the cosmic rays with energies E > Eth = 5.5×1019 eV. These show a correlation with the distribution of nearby extragalactic objects, including an apparent excess around the direction of Centaurus A. If the particles responsible for these excesses at E > Eth are heavy nuclei with charge Z, the proton component of the sources should lead to excesses in the same regions at energies E/Z. We here report the lack of anisotropies in these directions at energies above Eth/Z (for illustrative values of Z = 6, 13, 26). If the anisotropies above Eth are due to nuclei with charge Z, and under reasonable assumptions about the acceleration process, these observations imply stringent constraints on the allowed proton fraction at the lower energies.

AB - The Pierre Auger Collaboration has reported evidence for anisotropy in the distribution of arrival directions of the cosmic rays with energies E > Eth = 5.5×1019 eV. These show a correlation with the distribution of nearby extragalactic objects, including an apparent excess around the direction of Centaurus A. If the particles responsible for these excesses at E > Eth are heavy nuclei with charge Z, the proton component of the sources should lead to excesses in the same regions at energies E/Z. We here report the lack of anisotropies in these directions at energies above Eth/Z (for illustrative values of Z = 6, 13, 26). If the anisotropies above Eth are due to nuclei with charge Z, and under reasonable assumptions about the acceleration process, these observations imply stringent constraints on the allowed proton fraction at the lower energies.

KW - Anisotropies

KW - Chemical composition

KW - Pierre auger observatory

KW - Ultra-high energy cosmic rays

UR - http://www.scopus.com/inward/record.url?scp=84899577280&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84899577280&partnerID=8YFLogxK

U2 - 10.7529/ICRC2011/V02/0868

DO - 10.7529/ICRC2011/V02/0868

M3 - Paper

AN - SCOPUS:84899577280

SP - 137

EP - 140

T2 - 32nd International Cosmic Ray Conference, ICRC 2011

Y2 - 11 August 2011 through 18 August 2011

ER -

Anisotropies and chemical composition of ultra-high energy cosmic rays using arrival directions measured by the Pierre Auger Observatory

Abstract

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Keywords

ASJC Scopus subject areas

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